One of the most important diseases of rubber tree is Corynespora Leaf Fall (CFL) disease, caused by Corynespora cassiicola fungus. The pathogen can attacks in all of rubber plant growth stages, lead to significant decrease of latex production and moreover it is causing plant death. Using resistant clones as a planting material is the most effective and economical way to prevent CLF disease. Therefore identification of resistant clones become the main strategy in the management of CLF disease.

In relation to those, Micha Graciana Devi have raised some more questions and here are hers:

“Sore Pak, apa kabar? I’m sorry to message you informally via facebook since I don’t know your email address. I do have some questions regarding the post that you have responded on linkage drags. https://www.researchgate.net/post/How_we_can_remove_linkage_drags. Mr. Sidhu mentioned complete linkage drag, however, I’m not really sure to what extent do you define whether a linkage drag is near or complete? is it based on the distance between the markers in the map?”

[Effectiveness of poly ethylene glycol (PEG) to characterize the response of soybean genotypes against drought stress]

ABSTRACT

Polyethylene glycol (PEG) solution is able to homogeneously reduce water potential, therefore, it can be used to imitate soil water stress. The objectives of this research were to determine the effectiveness of PEG solution to characterize and evaluate the tolerance of three soybean genotypes against drought stress at vegetative growth stage. Soybean seedlings were grown on semi hydrophonic system using greenleaf as supporting medium. The seedlings were watered with half strength of MS medium for 14 days, followed by half strength MS medium containing either 0%, 5%, 10%, 15% or 20% of PEG until harvesting period.

Xenia is a phenomenon usually associated with phenotype characters controlled by a single recessive gene. The genotype of pollen donor directly determines the phenotype of fruits or seeds harvested from female recipients. Kopyor coconut is a unique coconut mutant and its formation is an example of xenia, since the genotype of the pollen donor determines the phenotype of the harvested nuts. The objectives of this research were to evaluate xenia in two types of kopyor coconuts (i.e. Kalianda Kopyor Tall and Pati Kopyor Dwarf), determine effects of homozygous KK normal and heterozygous Kk Kopyor coconut ratio, and effects of homozygous KK normal coconuts removal from mix population on yield of Kopyor nuts.

Phalaenopsis orchid is one of the famous genera in Orchidaceae family which have high economic value. Phalaenopsis breeding needs to be developed intensively to fulfill market demand for new varieties. The objective of this study was to obtain the information of morphological and biochemical diversity of a collection of Phalaenopsis orchid which will be useful for Phalaenopsis breeding. Plant materials used were 10 genotypes of Phalaenopsis with various petal colours of white, yellow, pink, deep pink, purple, or combination of yellow and brown. Morphological diversity of 10 genotypes were analyzed based on qualitative and quantitative characters following UPOV guidance for Phalaenopsis, while biochemical diversity was based on pigment content such as chlorophyl, anthocyanin, and carotene in plant roots, leaves and flower petals.

Kopyor coconut is a natural mutant that has abnormal endosperm development. For the first time several genes that were suspected to be related to kopyor trait were identified based on the chemical compounds of the endosperm that different from that of normal coconut. Sucrose synthase (SUS), Stearoyl acyl carrier protein desaturase (SACPD), and Absicid acid insensitive (ABI) genes were isolated and analyzed. Four DNA fragments with length of 746, 738, 780, and 687 bp (CnSus1A, CnSus1B, CnSus2A, and CnSus2B) were obtained from SUS gene. Sequence analysis at DNA and amino acid level showed that CnSus1A, CnSus1B, CnSus2A, and CnSus2B were classified into monocot SUS group with non-grass SUS type. Isolation of SACPD gene resulted in one DNA fragment with DNA length of 716 bp.

Pati Dwarf Kopyor coconut originated from Pati, Central Java is one of the Kopyor coconut populations from Indonesia. Three varieties of Pati Dwarf Kopyor coconut, namely: Kopyor Green Dwarf, Kopyor Brown Dwarf and Kopyor Yellow Dwarf out of six potential varieties have been officially released as local superior varieties by the Minister of Agriculture, Republic of Indonesia at the end of 2010. The objectives of this research were to evaluate the stability of Kopyor fruit production among provenances of Pati Dwarf Kopyor coconuts. Evaluations were conducted especially for the three recently released varieties of Kopyor coconuts. Observations were carried out in 2011 and the collected data were then compared with Kopyor fruit production data collected in2009 -2010.